#include <iostream>
using std::cout;
using std::endl;

class Complex{
public:
    Complex(double real,double image)
    : _real(real)
    , _image(image)
    {
        cout << "Complex(double,double)" << endl;
    }

    void print() const{
        cout << _real << " + " << _image << "i" << endl;
    }

    friend Complex operator+=(Complex & lhs,const Complex & rhs);
private:
    double _real;
    double _image;
};

Complex operator+=(Complex & lhs,const Complex & rhs)
{
    lhs._real += rhs._real;
    lhs._image += rhs._image;
}


void test0(){
    Complex c1(1,2);
    Complex c2(4,5);
    c1 += c2;
    c1.print();
}

int main(void){
    test0();
    return 0;
}
